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Julius Werner ee87885343 cbfs-compression-tool: Fix minor edge cases in algorithm type parsing
This patch adds two minor improvements to the way cbfs-compression-tool
parses the compression algorithm type that is passed through the -t
option of the 'compress' subcommand. These improvements are intended
to prevent accidents and unexpected behavior when using the
cbfs-compression-tool, in particular in automated contexts such as a
Makefile rule.

In the first part of this patch, a return statement is inserted after
the 'if (algo->name == NULL)' check of the compress() function. This
causes the function to exit immediately and subsequently abort the
program when the algorithm type was not detected correctly. Previously,
execution would continue with the 'algo' pointer pointing to the zeroed
out stopper entry of the types_cbfs_compression[] array. The ultimate
effect of this would be to pass 0 as 'algo->type' to the
compression_function() function, which happens to be the same
enumeration value as is used for CBFS_COMPRESS_NONE, leading to a valid
compression function result that matches the behavior of no compression.
Thus, if a script calling cbfs-compression-tool compress contained a
typo in the -t parameter, it would continue running with an unintended
compression result rather than immediately exiting cleanly.

In the second part of this patch, the strcmp() function is replaced with
strcasecmp() when comparing 'algo->name' with the 'algoname' parameter
that was passed to the compress() function. strcasecmp() uses an
identical function signature as strcmp() and is thus suitable as a
drop-in replacement, but it differs in behavior: rather than only
returning a result of 0 when the two NULL-terminated input strings are
character by character identical, the strcasecmp() function applies a
weaker concept of identity where characters of the latin alphabet
(hexadecimal ranges 0x41 through 0x5a and 0x61 through 0x7a) are also
considered identical to other characters that differ from them only in
their case. This causes the -t parameter of cbfs-compression-tool
compress to also accept lowercase spellings of the available compression
algorithms, such as "lz4" instead of "LZ4" and "lzma" instead of "LZMA".
As an unintended but harmless side-effect, mixed-case spellings such as
"lZ4" or "LZmA" will also be recognized as valid compression algorithms.
(Note that since the character "4" (hexadecimal 0x34) of the "LZ4"
compression type name is not part of the above-mentioned ranges of latin
alphabet characters, no new substitutions become valid for that part of
the "LZ4" string with this patch.)

Change-Id: I375dbaeefaa0d4b0c5be81bf7668f8f330f1cf61
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/26389
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
2018-05-21 13:25:49 +00:00
3rdparty 3rdparty/blobs: Update submodule marker for Intel microcode updates 2018-05-15 13:19:19 +00:00
Documentation Documentation: Add lesson1 from the wiki 2018-05-20 19:12:52 +00:00
configs configs: add PC Engines apu2 sample configuration 2018-05-19 16:55:56 +00:00
payloads libpayload: Fix payload .bss corruption 2018-05-21 04:48:28 +00:00
src nb/intel/nehalem: Fix smashed stack in romstage 2018-05-21 13:25:24 +00:00
util cbfs-compression-tool: Fix minor edge cases in algorithm type parsing 2018-05-21 13:25:49 +00:00
.checkpatch.conf .checkpatch.conf: Ignore CORRUPTED_PATCH lint 2017-10-29 10:11:58 +00:00
.clang-format clang-format: Update .clang-format to be compliant with linux kernel coding style 2018-04-23 09:26:08 +00:00
.gitignore Documentation: Add support for building with Sphinx 2018-04-26 12:25:03 +00:00
.gitmodules Set up 3rdparty/libgfxinit 2016-10-29 01:35:03 +02:00
.gitreview
COPYING
MAINTAINERS MAINTAINERS: change second PC Engines maintainer 2018-03-21 18:25:49 +00:00
Makefile Makefile: Add filelist to help 2018-01-29 15:35:11 +00:00
Makefile.inc Makefile.inc: disable warnings on unaligned struct members 2018-05-20 12:11:28 +00:00
README README: Update requirements 2017-06-27 17:04:32 +00:00
gnat.adc
toolchain.inc toolchain: Always use GCC for Ada sources 2017-09-23 10:57:40 +00:00

README

-------------------------------------------------------------------------------
coreboot README
-------------------------------------------------------------------------------

coreboot is a Free Software project aimed at replacing the proprietary BIOS
(firmware) found in most computers.  coreboot performs a little bit of
hardware initialization and then executes additional boot logic, called a
payload.

With the separation of hardware initialization and later boot logic,
coreboot can scale from specialized applications that run directly
firmware, run operating systems in flash, load custom
bootloaders, or implement firmware standards, like PC BIOS services or
UEFI. This allows for systems to only include the features necessary
in the target application, reducing the amount of code and flash space
required.

coreboot was formerly known as LinuxBIOS.


Payloads
--------

After the basic initialization of the hardware has been performed, any
desired "payload" can be started by coreboot.

See https://www.coreboot.org/Payloads for a list of supported payloads.


Supported Hardware
------------------

coreboot supports a wide range of chipsets, devices, and mainboards.

For details please consult:

 * https://www.coreboot.org/Supported_Motherboards
 * https://www.coreboot.org/Supported_Chipsets_and_Devices


Build Requirements
------------------

 * make
 * gcc / g++
   Because Linux distribution compilers tend to use lots of patches. coreboot
   does lots of "unusual" things in its build system, some of which break due
   to those patches, sometimes by gcc aborting, sometimes - and that's worse -
   by generating broken object code.
   Two options: use our toolchain (eg. make crosstools-i386) or enable the
   ANY_TOOLCHAIN Kconfig option if you're feeling lucky (no support in this
   case).
 * iasl (for targets with ACPI support)
 * pkg-config
 * libssl-dev (openssl)

Optional:

 * doxygen (for generating/viewing documentation)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig' and 'make nconfig')
 * flex and bison (for regenerating parsers)


Building coreboot
-----------------

Please consult https://www.coreboot.org/Build_HOWTO for details.


Testing coreboot Without Modifying Your Hardware
------------------------------------------------

If you want to test coreboot without any risks before you really decide
to use it on your hardware, you can use the QEMU system emulator to run
coreboot virtually in QEMU.

Please see https://www.coreboot.org/QEMU for details.


Website and Mailing List
------------------------

Further details on the project, a FAQ, many HOWTOs, news, development
guidelines and more can be found on the coreboot website:

  https://www.coreboot.org

You can contact us directly on the coreboot mailing list:

  https://www.coreboot.org/Mailinglist


Copyright and License
---------------------

The copyright on coreboot is owned by quite a large number of individual
developers and companies. Please check the individual source files for details.

coreboot is licensed under the terms of the GNU General Public License (GPL).
Some files are licensed under the "GPL (version 2, or any later version)",
and some files are licensed under the "GPL, version 2". For some parts, which
were derived from other projects, other (GPL-compatible) licenses may apply.
Please check the individual source files for details.

This makes the resulting coreboot images licensed under the GPL, version 2.